A Help with force & pressure on spine while bench pressing weights

Hey everyone. I've never been very good at math/science so I'm seeking a little help from this forum in hopes that there is someone out there who can provide me or guide me to an answer. What I'm trying to figure out is the difference in force or pressure exerted on the human spine for an average adult male while doing a bench press on two different surfaces. If we use a length of 78 cm for spine length. A body weight of 90.72 kg. A bench press weight of 102.06 kg. Distance the weight bar travels 46 cm (downward only). Surface area is 1600 cm. What is the maximum force on the spine on a very hard surface (little to no compression...like a wood)? What is the maximum force on the spine on a very soft surface (like an air cushion)? Any help here would be incredibly appreciated. Thank you so much.